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by Uketello



Category: Undertale (Video Game)
Genre: Alternate Universe - Swapfell, Brainwashing, Drug Use, Kidnapping, M/M, Possible fontcest??, Rape/Non-con Elements, Swapfell Sans, Swapfell Sans is insane, Underfell Sans, Underswap Papyrus, Underswap Sans
Language: English
Status: Completed
Published: 2018-01-17
Updated: 2018-01-17
Packaged: 2019-03-06 02:12:16
Rating: Mature
Warnings: Rape/Non-Con
Chapters: 1
Words: 2,312
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13401264
Author URL: https://archiveofourown.org/users/Uketello/pseuds/Uketello
Summary: When Swapfell Sans loses his brother, he falls to deep anguish and out of both anger and desperation. Wanting things back the way they use to be, he goes after the only one that's pretty close to being like his brother.





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**Author's Note:**

> Facts:
> 
> -Swapfell Papyrus is dead.
> 
> -Berry joined the Star Sanses. (Consisting of Dream and Ink)
> 
> -The drug used on Swap Pap was made by Swapfell Undyne.

Underswap Pap had blacked out from a blow to the head. He had lost consciousness but soon was regaining it as his eye sockets twitched and began to slowly open. He lets out a groan as all his vision was is a momentary blur. 

He could however make up what appears to be snow covered grass. However, It has some small stains of red. Was that...blood? 

He felt something trickle down slowly from his head and drip the ground. It caused the red stain to get a bit bigger. It would seem that answered his question. His head was bleeding!

It's probably from the blow he received. Not to mention he could still feel his head was in pain. He tried to reach for it but he yelps. He realizes his arms were in pain. He turn his head slowly and saw his right arm was stabbed into a rock wall by sharp tipped bones that were stained with his blood, turning again, his left arm was in a similar condition.

"Wh-What the?" He huffs out. If he tried to pull either of his arms he might break them and come right off! Heck, he could barely move them anyway. It was far too painful. He looked around. He was deep within the forest of Snowdin! It was dark but....he felt...in danger for some reason...the atmosphere here felt different. 

Was he even in his Snowdin? It almost felt like Underfell. Swap decided to call out to see if anyone was there. 

"Heeeyy!!" He tried calling out loudly hoping someone heard him. "Hah...hah...Someone!! Anyone!! Help!!" Swap began to call out for help as loud as he could manage. That's when he heard the crunching of snow. Someone was walking over. His footsteps getting closer and closer.

Swap tried to figure out who it was, squinting his eyes seeing a silhouette coming closer, and closer, and closer.

He feels he recognizes it. The round head, the tails of a neckerchief. Was it...? "S-Sans?" Swap smiles almost close to tearing up.

He hadn't seen his brother in months ever since he joined the Star Sanses and was off saving the day with them. 

"I kn-knew you wouldn't forget m--" But soon it was cut off as the figure got much closer....It wasn't his brother.

His expression dropped and was now soon both worried and furious. This guy has sharp teeth, and despite the armor being sort of similar to his brother's it was black with gold linings. His eyes were blue but had a hint of red on em at the center of the star pupils. He also wore shorts instead of pants with a skull belt and red boots. He had a menacing looking grin.

"Well, glad to see your finally awake!" The other chuckles. "You were sleeping for a looong tiiime~" Soon the other knelt near gripping Swap's chin roughly. 

"Augh! Wh-Who are you!?" Swap asked trying to pull away from his grip.

"Myeh heh heh!" The other had a laugh like Blueberry's but different and the tone was sinister. "My name is Swapfell Sans, you are in MY world~ In fact Papy, Im the one that brought you here." 

Swaps groaned out of annoyance and asked. "Wh-Why!?" He tried to tug his arms but no use. They were stuck! He only yelped again from pain.

Swapfell wagged a finger. "No no. Bad boy! Your going to lose your arms, and we wouldn't want that now would we?" 

Swap only answered with a growl but soon yelled a bit. "What do you want!? Why did you do this to me!?"

The other only chuckled at the question. But then, in an eerie tone he replies. "You look just like him...ya know?"

Swap became confused and asked. "Wh-Who?" Suddenly he saw Swapfell summon a sharp bone. Before Swap could even react the other skeleton swung it down and left a scar on his eye socket. Swap let out a pained scream as more blood trickles down the new wound. 

"There we go!" Swapfell said joyfully. Swaps was shuddering in pain, tears well up and slide down his cheek bones. 

"Now Papy~ Lets go home." The other said as warmly sounded as he could. Swaps looked up with one eye confused but once again he was knocked unconscious.

_ _ _ _ 

Swapfell made changes to Swaps appearance. Black jacket replacing his orange one and had a fuzzy hoodie. He wore an orange sweater, black pants with knee holes and a spiked collar like the one Underfell Sans wore. 

Swapfell Sans looked him over grinning pleased. Swap Pap struggled from the ropes that bound him to the bed. The ropes had some essence of magic preventing Swap from getting free nor using his magic. He was also gagged, but it wasn't some piece of cloth. It was a red ball gag. Swap felt dirty just having the thing on his mouth. Who knows where it's been!? It also muffled any swears and or screams he tried to yell out. 

"Almost perfect. Lucky for you I patched you up Papy. Otherwise you'd have bled the bed. Or....should I say....YOUR bed." Swapfell reached over petting his bandaged skull, arms as well bandaged. Swap moved his head away causing Swapfell to grown and brought up a crop (a special kind of whacking stick for horses) he then brought it down to his bandaged arm.

Swap ends up yelping in pain. "Bad brother! That's not how you behave! You love when I treat you like that. My puppy~" Swapfell scolded. 

Now it made sense to Swaps, this guy....wanted him to become his brother. But why? He doesn't understand, doesnt this guy have his own Papyrus!? Swaps regain his motion to struggle.

"Tsk...your truly a stubborn one aren't you?" Swapfell then sat near the bed. He lifted up the orange sweater exposing Swap's bones. Swap gasped at this. Was this guy seriously going to violate him!? 

"Mmmphh!! Mm!!" Swap tried to yell out 'no' but of course the gag muffled it. He arched himself trying to stop Swapfell from even laying a hand on him.

Swapfell growled and something Swap didn't expect just suddenly happened. The collar around his neck electrocuted him. Swap screamed into his gag as he felt shocks throughout his bones. Swapfell only watched smirking. 

Not only did this feel painful but it had a mix of pleasure in it as well. He didn't want to feel this! This felt awful! He felt like his body was being abused and violated. Eventually the static wore off leaving Paps just panting and shuddering. 

"Ahh....hah....haah....a-ahh..." He was shaking everywhere. But what felt odd was the center of his pelvis. 

Swapfell took notice the bulging orange center. "See? Just like my brother. Even when in pain he still finds a way to feel all good and tingly" Swap had not enough fight in him to stop Swapfell Sans from putting a hand on his bulging member. Swapfell began giving a good rub to it and Swap was too weak to resist letting a few moans slip from his gag.

"Mmph...mmm!...mmpmh!" He shudders at the touch. The shock made Swap feel sensitive. He felt sensitive all over. Even touching his member gave him pleasure. 

Swapfell gave it a good squeeze causing Swap to jolt and moan out more. He weakly shook his head.

"Mm! Shto..ph! Sth..shht..oph!!" Swap tried to get him to stop but Swapfell unizipped his pants exposing his erect member that was already soaked to the tip.

"Oh brother~ Your already so hard~" Swapfell Sans began to rub the base of his member to give a good squeeze. Swap ends up moaning again shaking his head. 

"Tsk! Stop being so stubborn! I doubt your 'brother' gave you this kind of pleasure now did he? If he ever cared about you he wouldn't have left you!" Swapfell struck a cord there. Hearing that Swap began to tear up. 

This made Swapfell happy. He can fully take advantage of this. "Here brother~ Let me show you what it's like to be pleased. Let me take good care of you~"

Swapfell positioned himself and took in Swap's entire member within his mouth.

"Mmph!!?" Swap was alarmed and tried to struggle a little but his collar was already sparking a bit as a warning. Being afraid of another shock Swap had no choice but to let Swapfell do what he wants him. Swap could only whimper helplessly as Swapfell Sans licked around his member and over the tip. 

Swap was shuddering from such unwanted pleasure. He couldn't resist moaning and getting flustered from the humilation of being fucked by this evil version of his brother. 

"Aahhmm...see? Your being such a good boy~ " Swapfell engulfed his cock once again. Licking around and getting the member nicely wet and soaked with his red saliva. Suckling up the cum that leakrled from the tip.

Swap whimpered and moaned helpless. He felt something in his member build up and soon he made released. Swap arched and moaned out vibrating the ball gag.

Swapfell Sans just swallowed every drop and with a pop he releases Swap's member. "Ahh~! Too good!"

Swap just started sobbing feeling disgusted that it felt good. Swap turn his head to the side.

But it wasn't over yet. Swapfell was far from done. He stood up and headed for the drawer nearby. Swap tried to see what he was doing as he panted, then Swapfell lifted up a syringe. 

Swap panicked squirming within his bounds. 

"Your wondering what this is brother?" Swapfell asked. Swap shook his head frantic. Swapfell Sans looked over him.

"Don't worry.....your about to find out~" With one hand he pushed down his head and injected the strange concoction within the syringe into the crack of Swap Pap's neck spine. Swaps screeched in panic but it was too late. All of it was injected and Swapfell released his head. 

_ _ _ _US!Pap POV section_ _ _ _

Who was that?

Further in the distance....

Through the snow storm.....

I see someone familiar...

I cry out for them yet they kept walking away from me...

He was smol, round and adorn in a silver armor..

He was someone important to me but....He left.

But then...

He...came back?

He looked different...

He wore black and he seemed confident. I felt his red gloves hand to my cheek. Just carressing it...

I felt tears in my eyes....

Brother?

No....He wasn't just my brother....

I'm beneath him....

I obey him...

"...My...."

_ _ _ _End of POV_ _ _ _

Swapfell Sans felt joyful today. It's been about a month. He was watching his favorite show downstairs. Sipping up some wine. He didn't feel like sitting on the sofa though. 

"Pap!! Come here! I demand a chair and I refuse to use the sofa today! Too much change saved in there..."

Slowly someone came out of the kitchen. Swapfell smiled as the other slugishly came and knelt on the floor in a crawling position.

"L-Like....th-this....m-my lord?" Pap asked. Swapfell Sans nodded in approval. 

"Good!" He sits onto his back. Luckily Sans wasn't that heavy. 

Papyrus looked up at Sans. "M-M...My...lord..." He was shuddering.

"Myeh haha! What's wrong brother? Are you getting excited again?" 

Pap answered with a nod. 

"Then stick your tongue out like a dog and beg for it." Sans commanded. 

Pap laps out his orange tongue panting. "Hahh...ha...P-Please?" He begged shakily.

Swapfell grinned and before he could give Pap what he wanted he heard loud knocking on the door. 

"Ughh...What the Hell!?" Sans stood up. "Stay like that Pap and DO NOT move a muscle!" 

"Y-Yes m-m'lord..." Pap remained where he's at, not even bothering to look at the door.

Sans opened the door. "Who is it!?" He said grumpily only to be greeted by a VERY worried Blueberry (Underswap Sans) and an equally worried but frustrated Red (Underfell Sans)

"Red? Berry? Why are you two here?" Raspberry (Swapfell Sans) replied.

"It's my brother Papyrus! He....He's gone!" Blueberry responded feeling like he might cry. Red places a hand on his shoulder trying to call him down.

"Take it easy Berry...we'll find him." Red soon looked to Raspberry. "Ya hadn't seen him have ya? He just suddenly vanished from Underswap."

"No. Not like he's any of my bussiness now is he?" Raspberry's attitude was rather salty.

"Jeez what's got your shorts in a twist all of a sudden Raspberry?" Res responded.

"You interrupted me and MY brother during watching TV!" Raspberry pointed to Pap whom was on the floor near the couch.

Berry gasped. "Why is he like that is he okay?" Berry just let himself in immediately.

"Hey!" Raspberry tried to stop him til Red responded. 

"Using him fer a chair again? Ya seriously need ta lighten up on yer bro. Even boss doesn't make me do that shit." 

"That's because Edge's ass is too big ta carry." Raspberry rolled his eyes.

"Heeeeyy!" Red looked at him annoyed.

Berry went near Papyrus. "Gosh...are you okay?"

He checked on him. Pap looked scared and shudders as Berry tried to touch him.

"No no...It's okay...I'm friendly, see?" Berry patted his head. Papyrus purred from the gentle touch....

It felt familiar to him....somehow. 

Soon he and Berry made eye contact....

Upon that happening, Berry's smile dropped. He looked shocked. 

"P.....Papyrus?"

_ _ _ _ _ _

Aaaaaand that's all folks! 

To anyone whom actually does read this I wanna see how you guys would continue it. May it be a happy end or not. :3 

Just link me though or credit me if you do. And yes this was based off someone's comic on tumblr.


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